Dispensers and cabinets for dispensing individual sheets of paper products, for example toilet tissue, from an internally stored stack of the products are known in the art. Commercial examples of such dispensers include the line of SaniTouch(copyright) bath tissue dispensers from Kimbery-Clark Corporation. The industry is continuously seeking ways to improve such dispensers, especially as to ease and reliability of use by the public, and simplicity and cost from a manufacturing standpoint.
Particular problems arise in use of such cabinets or dispensers for stacks of relatively high absorbency and low tensile strength paper products, such as bath or toilet tissue. For example, when a maintenance technician over-fills or xe2x80x9cstuffsxe2x80x9d the dispenser upon refilling, the stack becomes compressed against the bottom dispensing surface and it becomes very difficult for a user to pull individual sheets out of the dispensing throat. The sheets will tear and the user is tempted to grasp and pull xe2x80x9cclumpsxe2x80x9d of the product out of the dispenser. Preventing over-fill conditions is an ongoing issue and at least one solution is described in U.S. Pat. No. 4,938,382. The ""382 patent describes a dispenser for stacked folded sheets incorporating a mechanical anti-stuff feature to relieve compressive pressure in the stack resulting from an over fill condition.
Conventional dispensers also typically include front doors or panels that swing open to provide access for refilling the dispenser. This requires space for the door or panel to swing to the fully open position, thus limiting use of the dispensers in relatively tight confined spaces. Also, locks and key mechanisms must be provided to secure the door or panel and to deter vandalism. Such devices add to manufacturing costs, must be serviced and maintained, and require the maintenance personnel to keep track of keys and the like for opening the dispenser.
The industry is constantly seeking improved dispensers, particularly for dispensing stacked sheets of bath or toilet tissue. The present invention offers such an improved dispenser and addresses certain noted drawbacks of conventional dispensers.
Objects and advantages of the invention will be set forth in detail in the following description, or may be obvious from the description, or may be learned through practice of the invention.
In accordance with the invention, a dispenser is provided for dispensing individual sheets of paper product from a stack of such sheets. The dispenser is not limited to any specific type of paper product, but is particularly suited for dispensing bath tissue and toilet tissue. The dispenser includes an external housing defining an internal compartment with a bottom opening provided therein. The shape and configuration of the external housing is not a limiting feature of the invention, and the external housing may take on any aesthetic shape and may be made of any suitable material.
In one embodiment of the invention, a module is slidably received in the housing compartment through the bottom opening. The module is sized to receive a stack of the folded sheet products to be dispensed. For example, the module may have side walls, a bottom surface, and a back wall defining a generally elongated stack location for loading a stack of the paper products into the module. The bottom surface of the module is provided with a dispensing throat. The throat may take on various configurations and, in one particular embodiment, the throat has a generally trapezoidal shape.
The module is moveable vertically within the housing compartment from a loaded position wherein, in one embodiment, the module is inserted substantially entirely within the compartment with the dispensing throat being accessible to a user through the bottom opening of the housing. The module is vertically moveable from the loaded position to a refill position wherein the module is slid down and out of the compartment a sufficient distance to allow a maintenance technician to load a refill stack of the paper products into the module. Once the module is refilled, the maintenance technician simply pushes the module vertically back up into the housing.
A latch mechanism may be provided between the module and the housing to releasably lock or hold the module within the housing at the loaded position. To release the module from the loaded position, the maintenance technician simply releases the latch mechanism.
The invention contemplates embodiments of the dispenser wherein the housing compartment is sized to receive a single module, or multiple modules. For example, a dual module dispenser is contemplated wherein two modules are received side-by-side within the housing.
In a particularly useful embodiment, the module is slidably and lockingly engaged with the housing so that the module is moveable between the loaded and refill positions without being removed completely from the housing. In other words, in the refill position, the module extends down and out of the housing but is still retained by the housing. In this embodiment, a protrusion or a channel may be provided on one of the walls of the module. The protrusion or channel may lockingly engage with a complimentary channel or protrusion defined on one of the walls of the housing. For example, the module may include a back wall having at least one resilient protrusion extending therefrom. This protrusion may be resilient so as to allow for initial loading of the module into the housing. The protrusion may engage and slide in a channel defined in a back wall of the housing. The protrusion and channel have a shape so that as the module slides vertically down from the loaded position to the refill position, the protrusion slides along the channel. At the end of the channel, the protrusion prevents the module from being pulled or falling out of the housing.
It may also be desired to incorporate a mechanical anti-stuff mechanism in the module to restrict the height of the stack of sheets loaded into the module. This anti-stuff mechanism may take on various designs, and may include known devices. In a particularly unique embodiment of the invention, the anti-stuff feature includes a top plate that moves automatically in the stack location to a reduced vertical height upon movement of the module to the refill position. The plate is held in this position until the module is moved back to the loaded position wherein the plate is released and free to move upwards in the stack location. In this manner, any compressive forces on the stack resulting from an overfill condition are relieved. The top plate may be moved and held by any number of mechanisms, including at least one cam mounted on the module which is in mechanical communication with the top plate. This cam may be contacted and engaged by a cam surface defined on a wall of the housing such that the cam contacts and engages the cam surface upon movement of the module to the loaded position.
According to another unique feature of an embodiment of the invention, the module may be provided with a moveable stack lift mechanism disposed adjacent to the bottom surface of the module. The lift mechanism may be, for example, a bar disposed across the width of the module forward of the dispensing throat. At least a forward facing portion of the stack of sheets is positioned on top of the lift mechanism upon refilling the module. Upon insertion of the module into the housing to the loaded position, the lift mechanism automatically moves from a first position adjacent the bottom surface of the module to a second position displaced vertically upwards from the bottom surface. In this manner, the portion of the stack resting on the lift mechanism is moved upwards and away from the bottom surface of the module. It has been found that this orientation of the stack within the module relieves compressive forces of the stack against the bottom surface of the module and provides for more efficient dispensing of individual sheets through the dispensing throat. The lift mechanism, i.e. bar, may be actuated or moved by any number of mechanical arrangements. For example, the bar may include side arms that are pivotally mounted to respective sides of the module. The side arms may be engaged and moved by cam surfaces defined on the housing upon movement of the module to the loaded position.
The present invention also includes a stand alone module intended for use in combination with a dispenser housing to dispense a stack of folded sheet products, as discussed above. In other words, an embodiment of the invention is the module without the associated dispenser housing. The module may be configured as described herein.
An alternative embodiment of the invention is any dispenser for dispensing a stack of folded sheet products incorporating the moveable stack lift mechanism as described herein. In other words, the inventive stack lift mechanism may be used in any type of dispenser and is not limited to a module/housing configuration. The invention includes any such uses of the moveable stack lift mechanism.